The shafts of sticks used in ice hockey, street hockey and other similar games conventionally have a rectangular cross-sectional shape, with rounded corners. The shafts are made of stripes of wood and glass fibre laminate, which is used to provide added strength. In addition to conventional shafts that contain wood, shafts known as composite shafts have been developed, which are substantially entirely made of fibre-reinforced plastic. In comparison with conventional wooden shafts, the advantage of composite shafts is their good weight to rigidity ratio and the fact that their rigidity can be adjusted in a controllable manner by varying the amount, quality and direction of the reinforcing fibres. Known composite shafts are manufactured by winding reinforcing fibres around a mandrel or a lightweight core. Due to the manufacturing process, this kind of shaft is provided with an oval cross-sectional shape. This shape has not, however, gained popularity among players, who prefer conventional sticks that have rectangular shafts. Composite shafts with a rectangular cross-sectional shape cannot be manufactured by winding, because the pressure caused by the wound reinforcing fibres is greater on the corners of the rectangle than on its sides. The binding material therefore tends to move away from the area of the corners, the corners thus forming the thinnest area in the cross-section of the shaft. In a known manufacturing method, a reinforcement fabric is wrapped around a mandrel, after which the blank is pressed and hardened in a mould or an autoclave. Also here the problem is that the tightly wrapped reinforcement fabric presses binding material away from the area of the corners, and the corners become weak. The corners are, however, the most critical area of the shaft, because they are subject to impacts during the game. An impact on the fragile corner may damage this kind of shaft structure relatively easily.